As he returns to work more than two years after being gravely injured in a shootout with the Marathon bombers in Watertown, MBTA Police Officer Dic Donohue says he is grateful and knows he is lucky to be alive.

"Sometimes I think about how crazy it was and how lucky I am to be alive and how lucky I was that certain people took certain actions," Donohue said. "You take one person out of the equation and I might not be sitting here."

In addition to returning to work, he was promoted to sergeant in a ceremony on Friday. The ceremony was attended by his family, including his father who pinned the sergeant's pin on him, and some of the people who helped save his life.

"(It) shows the great support I have had since day one, since the incident and the actual day of the Marathon bombing in 2013," Donohue said.

Donohue said he may be back to work, but he is still recovering from his injuries.

"Every day I wake up, I have pain and I have learned to manage that. And I look back a year and even a few months to see how far I've come," he said.

Donohue said he will be working in the special crimes unit, which deals primarily with drug and anti-terrorism cases.